Process for eliminating stain from color-yielding elements by treatment with aromatic aldehydes containing an acyl group



Patented May 4:,

PROCESS FOR ELIMINATING STAIN FROM COLOR-YIELDING ELEMENTS BY TREAT- MENT WITH AROMATIC ALDEHYDES CON- 7 TAINING ACYL GROUP Andrew Bradshaw Jennings, New Brunswick, N. J., assignor to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware No Drawing. Application August 23, 1945,

Serial No. 612,300

6 Claims. 1

This invention relates to color photography and more particularly to the elimination of color stain from colloid layers of photographic elements. Still more particularly it relates to a process and compositions for eliminating stain from photographic colloid silver halide layers of color yielding elements.

The most commercially practical methods of color photography at the present time utilize the principle of color coupling development of developable silver salt images. This principle has been known for many years and is described in Fischer United States Patent 1,102,028. Color formers are utilized in such processes which cou- Dle with the development reaction products of aromatic primary amino photographic developing agents to produce quinoneimine or 'azomethine dyes. This action takes place during the reduction of silver salts to metallic silver; the dyes being formed in situ with metallic silver images. The cOlOr formers can be used either in water-permeable colloid-silver halide layers or in aqueous developer solutions. Many variations and improvements on the process described in the Fischer patent have been proposed. In one of such processes the color formers are of relatively high molecular weight or are polymeric in nature and are incorporated in gelatino-silver halide emulsion layers. Because of their molecular'size and chemical constitution, they do not migrate during photographic processing. In another variation the color formers are placed in gelatin layers which are contiguous with gelatino-silver halide emulsion layers. A recent and novel process is described in United States Patent 2.397364. In this process hydroxylated polymer color formers are used as binding agents for silver salts. These color formers have the dual functio of producing color during color development and of being binding agents for the silver salts. They may be distinguished from gelatin and gelatin color formers in that they do not set and do not form gels.

A disadvantage which is common to all of the above processes is that a color fog or stain is formed during processing to form quinoneimine or azomethine dye images. When the exposed photographic silver halide layers are developed with a primary aromatic amino developing agent a dye fog is frequently formed in the emulsion layers. This is so because the developing agents Suffer oxidation to some extent by the action of air and the oxidized developer tends to couple with the color former at points or areas in the colloid layers of the photographic elements where no silver image is produced. Inaddition, in processing films of the above type it is frequently observed that there is a pronounced tendency for the generation of the color in the non-image areas of the colloid layers in the color yielding photographic elements when the. color developed element is treated with an oxidizing bleach solution used for the purpose of removing metallic silver and silver salts from the layers. This undesirable aspect results from a retention of small amounts of development reaction products of the aromatic primary amino developing; agents in the colloid layers following color coupling development. It is difiicult, if not impossible,- to remove the last traces of such reaction products by washing the-film in aqueous baths.

An object of this invention is to provide a simple and economical method of eliminating color stain from color-yielding photographic elements. Another object is to provide such a method which is applicable to all types of photographic elements utilizing color formersin the formation of quinoneimine or azomethine cl'ye images. Still other objects will be apparent from the following description of the invention.

The above disadvantages of the prior art process of color coupling development are overcome and the above objects are obtained by treating photographic silver halide emulsion layers containing quinoneimine or az'omethine dye images with a ketaldone containing in addition tothe amine-active group, that is, the carbonyl group of the aldehyde or ketone, at solubilizing group. Suitable solubilizing groups which may be present in the ketaldones include carboxyl, primary amide, amino, hydroxyl, sulfonicfacid, and primary sulfonamide groups; The photographic element containing such emulsion layers can be treated during the development of the metallic silver and quinoneimine or azomethine dye images or after development has been'completed. Thus the ketaldones containing the solubilizing groups are present at thetime, of formation of the silver images or subsequentlythereto but prior to the bleaching steps;

A photographic film element was prepared by depositing on a cellulose acetate film base a resulting layer there was coated a gelatin disper-- sion of 4,4'-bis-(1-naphthol-2-sulfoamidophenyl) ether. On the layer which formed was then coated a red-sensitive green blind gelatino-silver iodobromide emulsion layer. On the emulsion layer was coated a gelatin dispersion containing 4,4'-bis-(1-naphthol-2 sulfoamidophenyl) ether. On the layer which formed was then coated a gelatin dispersion of 4,4"-o-sulfobenzylidene-bis- (l-phenyl-3-methyl-5-pyrazolone). On the resulting color-yielding layer was then deposited a green-sensitive gelatino-silver iodobrom-ide V emulsion layer. Next was coated a gelatin disgelatin dispersion containing Ciillllllilllltfid silver and the mixed acetal of saliylaldehyde and benz aldehyde ortho sulfonic acid with polyvinyl acetal. A red-sensitive green blind gelatinoesilver halide emulsion was then coated on the layer formed. Next was coated a gelatin dispersion oi 4,4-o-sulfo-benzylidene-;bis-(1 phenyl-3-inethyl-fi-pyrazolone) to form a color-yielding layer. Next was coatedagreen sensitive"gelatino-silver iodobromi'de emulsion. on the resulting layer was then coated a gelatin dispersion of yellow colloidal silver and 4,4-o sulfo benzyliderie-bisl-giheriyl-B-metliyl-5 pyrazolone) Onthe layer formed was coated a gelatin dispersion containing benzoylacetfuroylacetbenzidide. On the resulting color-yielding layer was then coated a blue-sensitive 'ge'latino-silvei iodobromide emulsion. Threestrips of the resulting mm element were exposed to a main-colored object and then developed in a solution of the following-composition:

' Grams N-inethyl-p-aniiiiophnolJ/g sulfatein s- 5.0 Hydroquinohe g 5 i 7 to form ver ima e and washed. and r d- T e elemen attan. re d 9 hit lis ael 99 d v oped iea seliitiea e h $91 9 2; .0m .esit pei i-diet vl r li ev eneeiamie HQ? fied iii a nn te. 1 9 Pei s iiiin. PF9E' 5.0 Water e Qne r p W .WaSh$ ffQ-1 a. 12.Ii9d of 20' minutes hich wa re u reeid ies iie t e b nc o a pinkish sta aused??? a da i n Qf rac of eve oper ti t e 2 and i wa t ei bleache n %.pe a siuni ter i enide sel d xed m 25% hide s liiti'ee whe eb a lt ce e ma e armedwage as omew t a me b he pr se ce of a l ghtpink sh stainheother We stri s. wcrebethed' immed a ly afir o or. d veleiimeet in. a ueo en at. b ezal enysi i Q tho 'ulfo c c d e u'm a t an than ashed' r 5 and. 0 t s n e iv lr be e b each n a d fixin s la hs The' tr wbit had be n wa h d or 5 min tes hail a. tim f a pinkish t in bu h irin hi'q had been treated fer m nu e was flee. rom's ain- A cellulose nitrate hasewa's coated with a gelatin dispersion ofcomminuted'silv'er. 0n the piiion oritaining colloidal silver and 4,4'-o-suliobenzylideneebis -.(1-phenyl-3--methyl-5 pyrazclone). Next was coated a gelatin dispersion containing 'benzoylagetiliroylacetbenzidide. On the resulting colorryielding layer was then coated a blue-sensitive gelatino-silver iodobromide emulsion. The resulting multilayer film was exposed to a color sceneandthen developed in a developer solution prepared by admixing the followmg components:

Grams N-methyl-p-aminophenoLV sulfate 2.0 Hydrouu nope Sodi m gulfite'ianhydrousl 60.0 Sodium carbonate (anhydrous) 46.0 Potassiumhydroxide 3.5 Potassium thiocyanate 2.0

Water t0 IOQOec.

T e film w s ashed i l'iiiini t s in un in wa er an dried Af e exPQsure to white li h the film was develonedier 2.5 lili Ql ee n a saluiien 0 the enema peiepo ition;

. Gram -minoditth l an line dreghl r de ---e-..- Potassium'carb na e "71-.- 2 r asslem flij oeyena azaldehyde-wsul cnicas -0 Wa ertQ 09 ccxample HI a multilayer h m or the type disclosedin Example II was treated; in an aqueous solution conam ng 2% be e deh deeu io ie d a t the first and noncolor iormingdevelopment had been completed. Itwas'iound'tha t the orthosulfonio acid; could be used-in a concentration of 140% with good results. The film is immersed for a period of 2f-10 minutes and is substantially free from "color;- stain after photographic processing to a multicolor image has been "completed.

Example IV A l t i (i llfl' iia fi's bi Pi v i lvl alc h l in v bsit cf. 1 2 c ntin0 s n a 4% u t. smu i n a 2.0" moment selic laldehv 00 natts'qf 1 9m 1 M110 pa -ts h spliq' ic a'q d issti' l d @585 air 5 ou d l ithlflqo'pa bs -atenn and fi te d Th hite powder 'is Washed "by decantation in icon-part 5.1 portions of acetone'zfi times for 1 hour each, then filtered and dried to give 140 parts of a fine white powder." Ten parts of this powder is dissolved by stirring in 90 parts of 40% ethanol-water at 80 1 C. for one-half hour. To 40'parts of this solution is added 40 parts of water, parts of 1% aqueous sodium dodecyl sulfate, and 5 parts of ,con-' centrated ammonia water. The mixture is stirred at 45 C. while adding 20 parts of' 3N silver nitrate and 23 parts of 3N ammonium'bromide-f N'potassium iodide simultaneously during the five'minutes. After stirring a total of 15 minutes, the silver halide dispersion is, allowed to cool andmixed with 100 parts of acetone which precipitates the binding agent containing dispersed light-sensitive silver halides. After pouring off the liquid, the soft rubbery polymer mass is washed for one-half hour in running water to removethe soluble salts, then the remaining 60 parts of the original polymer solution is added, together with parts of ethanol and 1 part of 10% aqueous potassium bromide, and the whole mixture stirred at 58% C. for one-half hour, after which it may be used directly or stored. This light-sensitive dispersion is coated on paper or a film base and exposed to a colored object. It is then developed in the following solution:

Grams p-Aminodiethylaniline hydrochloride 4.0 Potassium carbonate 60.0 Potassium bromide 3.5 Sodium sulfite (anhydrous) 20.0 Benzaldehyde-o-sulfonie acid 5.0 Water to 1000 cc.

Sodium acetate grams 50 Acetic acid r-c 5 Benzaldehyde-o-sulfonic acid grams 5 Water to 1000 cc. Stop bath #3 Grams Sodium bus l 30 Benzaldehyde-o-sulfonic acid 5 Water to 1000 cc.

Fixing bath Sodium thiosulfate grams 240 Sodium sulfite dn 6 Boric acid do 6 Acetic acid (28%) cc 35 Potassium alum grams 12 Benzaldehyde-o-sulfonic acid do 5 Water to 1000 cc.

In place of the benzaldehyde ortho sulfonic acid and its sodium salt which are described in the above examples, there may be substituted various other ketaldones which contain solubilizing groups and are amine-active. Suitable additional compounds of this type include benzaldehyde-p-sulfonic acid, benzaldehyde-m-sulfonic acid, phthalaldehydic acid, hydroxybenzaldehyde, glyoxylic acid, alpha-naphthaldehydebeta-sulfonic acid, 2-naphthaldehyde-3-sulionic acid, 1-naphthaldehyde-4 sulfonic acid, l-naphthaldehyde-l-carboxylic acid, 2-naphthaldehyde- 3-carboxylic acid, pyruvic acid, levulinic acid and their alkali metal and ammoniumsalts, the amide of phthalaldehydic' acid, and benzaldehyde-o-sulfonamide.

The present process is not limited to the use of the particular photographic elements described above. On the contrary, it may be used with any multilayer or single layer or films having lightsensitive silver halide layers which utilize color formers in the chromogenic development of the silver salts. Thus the photographic elements described in United States Patents 2,319,369, 2,319,426, 2,320,422, 2,328,034, 2,282,001, 2,363,764, and various other patents may be similarly treated.

An advantage of the present invention is that it considerably reduces the time of aqueous processing of photographic elements. To be more specific, it reduces the time of washing to eliminate color stain to a'marked degree. l

A further advantage of the invention is that it provides a simple and economical means for eliminating color stain from photographic films utilizing chromogenic development. The elimination of all traces of such stain is highly important to the faithful reproduction of highlight tones in a color photograph. Another advantage of the invention is that it may be used with all types of photographic film elements which utilize color formers which form quinoneimine or azomethine dyes during color coupling development.

As a result of the fact that the efiective solubility of the color-coupling developers is increased, contact with the skin is less harmful since washing results in complete removal. This is highly important since many aromatic amines of this type are capable of producing certain varieties of dermatitis.

Asmany widely different embodiments of this invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not to be limited except as defined by the claims.

I claim:

1. The process which comprises treating a. photographic .element bearing at least one waterpermeable layer containing a color developed dye image taken from the group consisting of quinoneimine or azomethine dye images and silver and silver salts with an aqueous solution containing a compound taken from the group consisting of unsubstituted benzaldehyde and naphthaldehyde monocarboxylic and monosulfonic acids and their alkali metal and ammonium salts.

2. The process which comprises treating a photographic element bearing at least one waterpermeable layer containing a color developed dye image taken from the group consisting of quinoneimine or azomethine dye images and silver and silver salts with an aqueous solution containing an unsubstituted naphthaldehyde sulfonic acid.

3. The process which comprises treating a photographic element bearing at least one waterpermeable layer containing a color developed dye image taken from the group consisting of quinoneimine and azomethine dye images and silver and silver salts with an aqueous solution containing an unsubstituted benzaldehyde sulfonic acid.

4. The process which comprises color develop- 

